• 한국주조공학회지
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• 제32권2호
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• pp.91-97
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• 2012

The effects of Bi and Sb additions on the microstructures and casting properties in lead-free Cu-Zn-Sn broze were investigated. (1) When only Bi was added to the bronze, Bi was precipitated on the ${\delta}$ phase of ${\alpha}$ dendrite cell boundary. When Bi and Sb were added together, Bi was precipitated on the ${\delta}_A$ which was the Sb-rich area in the ${\delta}$ phase. (2) The addition of Sb accelerated the formation of ${\delta}$ phase, and when Sb, Bi and Pb were added, Bi and Pb were precipitated as mixed solution in the ${\delta}_A$ phase. (3) The combined addition of Sb and Bi resulted in the suppression of shrinkage due to the complementary effects of the mass feeding of ${\alpha}$-dendrite cluster covered with ${\delta}$ phase and sealing of micro-shrinkage in the ${\delta}$ phase by solidification expansion of Bi.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.731-734
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• 2013

Reduced tungsten bronze nanoparticles of ternary and quaternary compounds were prepared by adding sodium and cesium to crystal structures of tungsten trioxides ($Na_xCs_{0.33-x}WO_3$, x = 0, 0.11) while maintaining the overall alkali metal fraction at 0.33, in an attempt to control near infrared (NIR) shielding property in the particular wavelength range of 780 to 1200 nm. The structure and composition analysis of the quaternary compound, $Na_{0.11}Cs_{0.22}WO_3$, revealed that 93.1% of the hexagonal phase was formed, suggesting that both alkali metals were mainly inserted in hexagonal channel. The NIR shielding property for $Na_{0.11}Cs_{0.22}WO_3$ was remarkable, as this material demonstrated efficient transmittance of visible light up to 780 nm and enhancement in NIR shielding because of the blue-shifted absorption maximum in comparison to $Cs_{0.33}WO_3$.

• 한국의류산업학회지
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• 제16권4호
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• pp.511-519
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• 2014

The aim of this study is to develop fashion cultural product designs in order to promote the Iksan region by using motifs from the Mireuksaji, Iksan's most representative archeological site of Baekje culture. The fashion cultural products designs developed by applying cultural resources can be effective at enhancing our cultural identity. Adobe Illustrator CS4 and Adobe Photoshop CS4 were used to reconstruct motifs from the Sumakse tiles and the bronze horse figure in the Mireuksaji Museum. The Iksan brand slogan "Amazing Iksan" was combined with the bronze horse to emphasize the local cultural identity. The motifs from the Mireuksaji were modified and stylized to make different patterns and these patterns were repeated in various ways to be applied to necktie and scarf designs. The motifs for necktie designs were double-row chrysanthemum tiles and phoenix tiles, and the motifs for scarf designs were the double-row lotus tiles and the bronze horse artifacts. Different colorways were chosen and the value of each color was displayed in the CMYK percentages. As a result, eight necktie designs and twelve scarf designs were proposed. The motifs and patterns developed in this study can be used to introduce Iksan's distinct history as the birthplace of Baekje culture. It is also expected that the result of this study can advance the promotion of Korean traditional culture internationally.

• 보존과학회지
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• 제7권1호
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• pp.1-8
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• 1998

고려시대에 제작된 것으로 추정되는 금동과대의 제작기법을 규명하였다. 도금층은 형광X선 분석기를 이용한 mapping 결과, 아말감 기법에 의해 만들어지고, EDS 성분분석 결과 도금층은 금 뿐만 아니라 구리를 포함하고 있음이 밝혀졌다. 과대 뒷면에 고착된 섬유는 미세구조 관찰 결과 대마로 판별되었으며 그 직조방식은 나직이었다. 시문에 사용된 정은 삼각형 정과 반원형 정이고, 삼각형 정으로 문양의 테두리를 두른 후, 반원형 정으로 마무리를 지었다. 정의 시문철차를 조사하고 그 형상에 대해서 추정을 하였다.

• 한국표면공학회지
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• 제37권4호
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• pp.234-241
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• 2004

Cavitation erosion properties of the Cu-9Al-4.5Ni-4.5Fe alloys (Al-bronze) surface-modified by flame quenching process have been investigated. After flame quenching at above $T_{\beta}$, the surfaces of Al-bronze with $\alpha$ + $\textsc{k}$ structure have been changed into the $\alpha$ + $\beta$' martensite phases by the eutectoid reaction of $\alpha$ + $\textsc{k}$\longrightarrow$\beta$ followed by the martensite transformation of $\beta$\longrightarrow$\beta$'. As a result of cavitation test, the measured incubation time and erosion rate of the $\alpha$ + $\beta$' alloy was 1.2 times higher and 1.5 times lower, respectively, compared to those of the conventional $\alpha$ + $\textsc{k}$ alloys, showing a remarkable increase of cavitation resistance with the formation of $\beta$' martensite. This is attributed to a preferential erosion of the $\textsc{k}$ precipitates that show the lowest resistance among the $\alpha$, $\textsc{k}$, $\beta$' phases under cavitation loading.ases under cavitation loading.

• 한국세라믹학회지
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• 제38권12호
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• pp.1167-1173
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• 2001

텅스텐브론즈 구조를 가지는 Sr$_{x}Ba_{1-x}Nb_{2}O_{6}$(SBN) (0.3$\le$x$\ge$0.7) 세라믹스를 고상반응법으로 합성하고 Sr/Ba의 비에 따른 유전특성을 조사하였다. SBN 세라믹스는 Sr/Ba의 비가 증가함에 따라 상전이 온도는 낮아지고 상전이 온도에서의 최대 유전율은 증가하였다. 또한 SBN 세라믹스는 Sr 함량에 따른 relaxor 거동을 정량화하여 평가하였는데, Sr/Ba의 비가 증가할수록 유전율은 더욱 완만해지는 것을 관찰할 수 있었다. 이러한 실험 결과를 텅스텐브론지 구조를 가진 SBN 세라믹스의 결정구조 관점에서 해석하였다.

• 건축역사연구
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• 제17권5호
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• pp.7-22
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• 2008

The purpose of this study is to examine the function of wall posts in pit-houses in the Bronze Age, in the Kyung-nam Province. Wall posts were found as post-holes, created after wooden posts had decayed. In this research, the role of wall posts is newly defined from the perspective of a construction engineering. While existing studies in archaeology regard wall posts as sub-posts that support the roof of a pit-house, this study views wall posts as piles installed to support the soil wall, not as sub-posts. Based on the existing reports on excavation in prehistoric settlement sites by archaeologists, the study examines the remnants of the wall posts and remains after a fire. The main findings of this study are threefold. First, the wall posts were installed not as posts but as piles, cut sharply and hammered along the building lines of a pit-house. Second, wall piles were used to support the walls during earthwork, such as excavating and banking for low ground, mostly because a large amount of soil is often lost during the process. Third, wall piles were used as post piles of retaining walls that enabled the installation of transverse wall panels, which were used to prevent the soil loss.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.382-383
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• 2006

The tungsten bronze type of strontium barium niobate(SBN) thin film was synthesized by metal organic decomposion method for SBN stock solution and the SBN thin film process were deposited by spin-coating process on Pt-deposited si-wafer(100) by magnetron sputtering system. The thickness of SBN thin film was 150~200 nm and were optimized for rpm of spin-coater system. The structural variation of SBN thin film was studied by TG-DTA and XRD. The deposited SBN stock solution on annealing at $400{\sim}800^{\circ}C$ a pure tungsten bronze SBN phase and the corresponding. average grain size about 500~1000 nm influenced by annealing temperature. The piezoelectric properties of prepared SBN thin film, the remanent polarization value(2Pr) and coercive field was $1.2{\mu}C/cm^2$ and 2.15V/cm, respectively.

• 보존과학연구
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• 통권19호
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• pp.109-132
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• 1998

According to excavation of Imdang site, these sites were excavated place to a various of sites from Early lron period to the Koryo Kingdom. Artifacts to be conserved were excavated from A, D and E district. Metal artifacts were excavated from D and E district and lacquer ware artifacts were excavated from Adistrict. Metal artifacts including lacquer ware iron sword, imitative bronze mirror, Osujen and bronze artifact with letter and so on. Bronze artifacts were covered with soil and rust and performed consolidation after passivation treatment with Benzotriazole solution. Also, iron artifacts performed desalting treatment with 0.1M sesquicarbonate solution. After desalinization, adhesive of these artifacts were processed with Araldite(rapid type) after consolidation with20%∼30% NAD-10 solution. Lacquer ware artifacts remained fragments of lacquer to be all corroded and soiled. Therefore these artifacts retained its original form. Fragments of lacquer joined with Caparol 1%∼3% solution and the soil of relics coated with PSNY 3%∼6% solution. There were many kinds of lacquer were. Lacquer ware artifacts presumed to a string instrument that provide important clues for lacquer ware research. As for lacquer fragments inquire, paints grain size were $2∼5\mum$ and conformed to vanished three times.

• 박물관보존과학
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• 제3권
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• pp.1-7
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• 2001

송림사 전탑내 출토 금동제 사리장치(보물 제325-1호)는 일괄품인 유리제 사리기와 함께 매우 중요한 통일신라 사리장엄구의 하나로 꼽을 수 있다. 국립중앙박물관 보존실에서는 처리전 조사를 통하여 이 사리장치가 내부목재의 부후와 금동재질의 부식으로 인하여 상당히 위약해져 있음을 파악하고, 이를 보완하고 추후 발생할 수 있는 새로운 부식에 대한 예방에 중점을 두고 보존처리를 실시하였다. 또한 그동안의 송림사 전탑 출토 사리장치에 대한 정밀조사자료가 미비하여 정밀실측, 현미경조사 및 X-선 촬영 등의 세부적인 조사도 병행하였다.